The invention relates to a method for producing recombinant alpha-cyclodextrin glucosyltransferase (alpha-CGTase for short) by using bacillus subtilis, belonging to the technical fields of genetic engineering and fermentation engineering. The method specifically comprises the following steps: (1) constructing a recombinant bacillus subtilis genetically engineered bacterium of Bacillus macerans alpha-CGTase; and (2) optimizing fermentation conditions to obtain the optimal concentrations of key components of the medium, namely maltose, corn starch and yeast powder are respectively 15.5g/L, 13g/L and 20g/L, inoculating the recombinant bacillus subtilis in the medium, and carrying shaking culture for 36 hours, wherein the activity of the alpha-CGTase is 17.6U/ml. The method has positive meaning for early achievement of production of the CGTase by using the bacillus subtilis so as to satisfy application of the CGTase in foods.